I’m a little late this week, due to the Melbourne Cup holiday.
The following video I found on youtube is what inspired me for the card game from the previous post.
This video clearly shows that the smaller the batch, the quicker you process the work.
So, how does this relate to Agile, well, the sooner you can complete work – get it into production, or ready for production, the quicker you should finish your project. Think of each process as dev/test/preprod etc with the end goal ready for prod.
Don’t get fooled though, completing tasks themselves does not mean you are doing the above. For example, completing the development of a feature, completing another feature, completing another feature, then migrating to test. Testing feature 1, testing feature 2 etc. Where you have one card per task. ie, one card for developing feature one, then moving it to done once developed. In this case, you are still doing batches.
The above is for the life cycle of the feature. Not the task. If a feature is not being actively worked on, it should either be in the backlog, blocked or ready for migration to production or in production. Anything less and you are not doing agile.
For more information, look up continuous flow with regards to manufacturing, the Toyota Production System or Lean.
Another good book that explains this is “The Phoenix Project” which I’m currently re-reading (This time as an audio book).